2024/01/13 : not much new here... the height is about 8 cm now, very slow grow. Temps were too low so I added a flat 250W radiant heater and with DLI set to 20 now, it's about 24Β°C by day and 23Β°C by night : much better for vegetation! I water every 2 or 3 days with 1 L (about 300 mL runoff) and alternate elycitor/molasses.
Anyway, the seedling is now a plant so I made a quick video to celebrate!
2024/01/16 : it seems blueberry liked the hotter temp, buying this flat heater was best thing i've done this run... The height is 10 cm now and 4th node is here. I'm waiting for the 5th one to top it. I checked runoff pH and found 6.78, hoping it's OK.